Conventionally, toner containers such as one disclosed in Japanese Unexamined Patent Publication No. 2003-280344 are known as developer containers for containing developer. The toner container includes a toner discharge port and a rotary stirring member. Toner is discharged through the toner discharge port by rotation of the stirring member.
Japanese Unexamined Patent Publication No. 2009-265395 discloses a waste toner container for containing developer. The waste toner container includes a cylindrical container body having an outer circumferential portion formed with a helical groove. Collected toner is conveyed to one end of the container body along the helical groove by rotation of the container body.
In the toner container disclosed in Japanese Unexamined Patent Publication No. 2003-280344, toner is liable to remain in the region not affected by the rotational force of the conveying member, which makes it difficult to use up all the toner in the container. Further, even if the technique used for the waste container disclosed in Japanese Unexamined Patent Publication No. 2009-265395 is applied to the toner container, toner adhered to the groove will continue to rotate with the container body, so that the toner will remain in the container body. This has been a problem.